1. Field of the Invention
The present invention relates to a method of inputting information comprising at least one alphabetic character into an electrical unit, for example a vehicle navigation system.
2. Prior Art
Vehicle navigation units are known for operation in motor vehicles, which are available, for example, from Blaupunkt-Works GmbH, Hildesheim, Germany. These vehicle navigation units, after input of the vehicle destination, calculate a route from an actual vehicle location, which is determined, for example, by analysis of GPS (Global Positioning System) satellite signals, to the destination. The vehicle driver guides the vehicle along the calculated route by means of driver advisories.
Numerous methods are described in the Literature, for inputting the destination. For example, a destination can be specified by introducing a mark on a map representation by means of a controllable cursor. The destination can also be specified by inputting the destination name alphabetically in the actual unit e,g, made by Blaupunkt-Works GmbH.
For alphabetical destination input a keyboard or its equivalent is often available with current navigation units, by means of which the letters of the destination name are called up one after the other. A called-up letter is selected or designated by an acknowledging or confirming key. In order to make the input of the destination easier and faster, a known method designated as xe2x80x9cthinned-out spellerxe2x80x9d is used, in which the alphabet is reduced to those letters, which are included in destination names stored in a digital map data base having one or more letters which have already been input.
It is an object of the present invention to provide an improved method of inputting information to an electrical unit, especially a vehicle navigation unit.
This object and others, which will be made more apparent hereinafter, are attained in a method of inputting information comprising at least one alphabetic character in an electrical unit, especially a vehicle navigation unit.
According to the invention, after input of an alphabetic character the character itself, or, for the case in which one or more characters have already been input prior to the input of the alphabetic character, the character string formed by the first to the last input character, is compared with information entries in a comparison set of information, and, when the input character agrees with the first character of at least one of the information entries in the comparison set or when the character string agrees with the beginning of at least one of the information entries in the comparison set, this information entry is or these information entries are offered for input into the electrical unit. This method has the advantage that the input of information into the electronic unit, for example regarding a destination name into a vehicle navigation unit, is simplified and faster.
In a preferred embodiment the at least one information entry offered for input from the comparison set of information is erased when the at least one offered information entry is rejected for input in the electrical unit. This prevents already rejected information entries from being offered again during an input process. The rejection of information entries offered for input preferably can be triggered by input of an additional alphabetic character, so that no additional inputting effort is required for the rejection. For example, a rejection command is not necessary.
An additional acceleration of information input permits a suitable limitation of the comparison set of information to a fraction of the total amount, for example to a predetermined amount of previously input information.
It is also advantageous when the information entry offered for input from the comparison set is displayed with all characters of the information entry. This permits the user to control its input, when the information entry to be input is contained in the comparison set so that the electrical unit can reconstruct the information entry to be input from the characters already input at that time, or when input of additional characters is required.
Additional user-friendliness is obtained by displaying additional characters of the information entry offered for input that are retrieved by the electrical unit so that they are optically distinguishable from those characters of the information entry that were already actually input.